The swiss army knife of digital networks

This article describes a general discrete-signal network that appears, in various forms, inside many digital signal processing (DSP) applications. So the "DSP Tip" for this column is for every DSP engineer to become acquainted with this network. We show how the network\´s structure has the distinct look of a digital filter, a comb filter followed by a second-order recursive network. However, we do not call this unique general network a filter because its capabilities extend far beyond simple filtering. Through a series of examples, we illustrate the fundamental strength of the network: its ability to be reconfigured to perform a surprisingly large number of useful functions based on the values of its seven control parameters.